The present invention, in some embodiments thereof, relates to a seal for connecting two tubes or for checking the connection between two tubes.
U.S. Pat. No. 7,478,838 to McBee et al. describes a fitting for sealing against the inner surface of an inlet, including an elongated mandrel and one or more resilient bushings supported on the mandrel. The fitting has a first condition wherein the resilient bushing can be received within the inlet. The fitting can be actuated to a second condition where the resilient bushing expands radially to sealingly engage the inner surface of the inlet. When the inlet is sealingly engaged by the resilient bushing in the second condition, fluid may be admitted to the inlet through an axial bore in the mandrel. When the fitting is used to fill a pipe system, fluid supplied to the inlet may be pressurized to facilitate monitoring the pipe system for leaks. The fitting may include a sealing member configured to seal against a terminal end of the inlet when the bushing is radially expanded to seal against the inner surface of the inlet in the second condition.
U.S. Pat. No. 7,591,484 to McBee et al. describes a fitting for sealing against the outer surface of an inlet including a housing comprising a base and a closure defining a cavity within the housing. A resilient bushing is disposed within the cavity and is positioned between the closure and a piston slideably disposed in the cavity. The fitting has a first condition in which the inlet can be received within an inner diameter of the bushing through an aperture in the closure. The fitting can be actuated to a second condition in which the piston axially compresses the resilient bushing against the closure, thereby causing the inner diameter of the bushing to expand radially inwardly to sealingly engage the outer surface of the inlet. When the inlet is sealingly engaged by the resilient bushing in the second condition, fluid may be admitted to the inlet through a fluid passage in the housing.
U.S. Pat. No. 7,648,177 to Tombler Jr. et al. describes a method and apparatus for tight sealing between a first space and a second space. The second space is at least partially enclosed by a member. The method or apparatus includes or performs the step of creating or maintaining a pressure difference between a pressure in a third space at a seal assembly and pressure in each of the first space and the second space; and pushing, caused by the pressure difference, against a seal in the seal assembly to tighten sealing provided by the seal.